# Docs Impact Classifier

Use this skill to classify the documentation impact of a pull request diff, returning...

- Repository: https://github.com/microsoft/apm (4171 stars)
- Category: AI and agents
- License: MIT
- Last updated: 2026-10-30
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add microsoft/apm --skill docs-impact-classifier -g -a claude-code -y`
Codex: `npx skills add microsoft/apm --skill docs-impact-classifier -g -a codex -y`
Cursor: `npx skills add microsoft/apm --skill docs-impact-classifier -g -a cursor -y`
Gemini CLI: `npx skills add microsoft/apm --skill docs-impact-classifier -g -a gemini-cli -y`

## Description

Use this skill to classify the documentation impact of a pull request diff, returning one of three verdicts -- no-change, in-place edit, or structural change -- with bounded LLM cost. Activate as a sibling skill of docs-sync; the orchestrator calls this first, before any panel spawn, to keep cost floor at 1 LLM call when no docs work is needed. Reads .apm/docs-index.yml as the corpus map; never reads the full corpus.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# docs-impact-classifier

Single responsibility: given a PR diff and the `.apm/docs-index.yml`
corpus map, emit ONE classification verdict.

This skill is the cost gate for the entire docs-sync system. ~70% of
PRs should exit at verdict `no_change` with zero panel spawn.

## Architecture

This is a 3-layer funnel inside a single skill invocation:

- **L0 deterministic path gate** -- pure file-path matching, no LLM.
- **L1 symbol extraction + corpus grep** -- pure text processing, no LLM.
- **L2 LLM classifier** -- bounded ~8 KB context envelope, 1 call.

The skill returns the verdict from the earliest layer that can decide.

## Step 1: L0 deterministic path gate (no LLM)

Read `.apm/docs-index.yml` to load `no_impact_paths[]` and
`user_surface_paths[]`. Get the changed file list from the PR diff
(`gh pr diff --name-only`).

```
if every changed file matches no_impact_paths AND none match user_surface_paths:
    return {verdict: "no_change", confidence: "high", source: "L0", scope_pages: []}
```

This handles:
- Test-only PRs (`tests/**`)
- CI workflow PRs (`.github/workflows/**`)
- Doc-only PRs (`docs/**`) -- out of scope, docs-sync doesn't review docs PRs
- Primitive-only PRs (`.apm/**`)
- Script and meta PRs

Expected hit rate: ~70% of PRs short-circuit here.

## Step 2: L1 symbol extraction + corpus grep (no LLM)

If L0 did not exit, extract user-observable symbols from the diff:

- **CLI command names** -- grep diff for `^@click.command`, `^@cli.command`, or any `apm <verb>` mention in added/removed lines.
- **Flag names** -- grep diff for `^@click.option`, `--[a-z-]+` patterns.
- **Public API symbols** -- added/removed `def <name>` in `src/apm_cli/__init__.py` or `src/apm_cli/api/**`.
- **Schema keys** -- added/removed keys in `apm.yml`, `apm.lock.yaml`, `apm-policy.yml` parsers.
- **Error strings** -- added/removed string literals in user-facing error paths (look for `_rich_error`, `click.echo`, `raise ... Error(`).

The rest: https://github.com/microsoft/apm/blob/HEAD/.agents/skills/docs-impact-classifier/SKILL.md